Cummins
Cummins fault code
SPN 1043 / FMI 4
Cummins Fault Code 443: Accelerator Pedal Position Sensor Supply Voltage Circuit - shorted low
443 on Cummins engines means: Accelerator Pedal Position Sensor Supply Voltage Circuit - shorted low. The failure mode (FMI 4) is “voltage below normal, or shorted to low source”.
Lamp: Yellow
Engine may continue to run, but must be repaired the same day.
Code details
- Manufacturer
- Cummins
- Applies to
- Cummins QS-series electronic engines
- Fault code
- 443
- J1939 SPN
- 1043
- FMI
- 4 — Voltage below normal, or shorted to low source
- J1587 PID / SID
- S221
- Engine models
- QSB, QSC, QSL9, QSM11, QSX15
What to do next
- Read active and inactive codes with the OEM service tool and note the occurrence count.
- FMI 4 tells the shop the type of failure to test for: voltage below normal, or shorted to low source.
- Have a heavy-duty diesel technician confirm the fault against the engine or chassis service manual before replacing parts.
Get this code diagnosed
Send one request and nearby diesel shops and mobile mechanics can quote the repair.
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Related fault codes
- Cummins Fault Code 283 — Engine Speed/Position Sensor #1 (Crankshaft) Supply Voltage Circuit - shorted high
- Cummins Fault Code 284 — Engine Speed/Position Sensor #1 (Crankshaft) Supply Voltage Circuit - shorted low
- Cummins Fault Code 387 — Accelerator Pedal Position Sensor Supply Voltage Circuit - shorted high
- Cummins Fault Code 496 — Engine Speed/Position Sensor #2 (Camshaft) Supply Voltage
- International SA 33 SPN 1043 FMI 0 — Bias Voltage reading above normal range
- International SA 33 SPN 1043 FMI 1 — Bias Voltage reading below normal range
- PACCAR Fault Code P1644 — PCI ECU 5V Sensor Power Supply Circuit 2 – Voltage Too High or Short Circuit to Supply
- PACCAR Fault Code P1645 — PCI ECU 5V Sensor Power Supply Circuit 2 – Voltage Too Low or Short Circuit to Ground
Source: Cummins "Diagnostic Fault Codes For Cummins Engines", publication 80-1044 Rev 5/2013, page 13. See also OBD-II codes.